Second Chemical Identified in West Virginia Spill

Little Known About Long-Term Effects on Health

The company at the center of the chemical spill in Charleston, W.Va., that contaminated tap water for 300,000 people earlier this month confirmed Wednesday that a previously unidentified chemical was also in the storage tank that leaked.

Under order from state authorities, Freedom Industries Inc. disclosed the tank that leaked on Jan. 9 contained a small percentage of a proprietary chemical mixture called "PPH, stripped."...